Apparatus, method, and computer program product providing persistent uplink and downlink resource allocation

ABSTRACT

Apparatus, methods, computer program products, systems and circuits are provided that allow for persistent uplink and downlink resource allocations. A method includes: allocating resources to a user equipment for a data flow over a plurality of time intervals with a single signaling event at a wireless network radio network layer; and informing the user equipment of the allocated resources.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application claims priority under 35 U.S.C. §119(e) fromProvisional Patent Application No. 60/765,081, filed Feb. 3, 2006, thedisclosure of which is incorporated by reference herein in its entirety.

TECHNICAL FIELD

The exemplary embodiments of this invention relate generally to wirelesscommunications systems and devices and, more specifically, relate topacket mode transmissions of data between a wireless network and a userequipment (UE), such as a cellular phone.

BACKGROUND

The following abbreviations are herewith defined.

BTS base station

DL downlink (Node B to UE)

FDMA frequency division multiple access

IP internet protocol

L1 layer 1 (physical layer, PHY)

L2 layer 2 (medium access control, MAC)

L3 layer 3 (radio network layer, RNL)

LTE long term evolution of UTRAN

MAC medium access control (layer 2, L2)

Node B base station

OFDMA orthogonal frequency division multiple access

PDCP packet data convergence protocol

PHY physical layer (layer 1, L1)

QOS quality of service

RNL radio network layer (layer 3, L3)

RRC radio resource control

SAP service access point

SFN system frame number

TTI transmission time interval

UE user equipment

UL uplink (UE to Node B)

UTRAN universal terrestrial radio access network

VoIP voice over IP

A reasonable working assumption when considering UTRAN LTE, which maysometimes be referred to as 3.9 G, is that the system will primarilyrely on so-called one time allocations, where a serving cell explicitlysignals to a UE in every sub-frame where the UE is allocatedtransmission resources. The signaling to allocate transmission resourcescan be sent as part of a Layer-1 (physical layer) allocation table.However, the allocation table represents a signaling overhead thatconsumes some amount of the finite available bandwidth.

SUMMARY

In an exemplary aspect of the invention, a method includes: allocatingresources to a user equipment for a data flow over a plurality of timeintervals with a single signaling event at a wireless network radionetwork layer; and informing the user equipment of the allocatedresources.

In another exemplary aspect of the invention, a computer program productis provided. The computer program product has program instructionsembodied on a tangible computer-readable medium. Execution of theprogram instructions results in the following operations: allocatingresources to a user equipment for a data flow over a plurality of timeintervals with a single signaling event at a wireless network radionetwork layer; and informing the user equipment of the allocatedresources.

In a further exemplary aspect of the invention, a device includes: aradio network layer component configured to allocate resources to a userequipment for a plurality of time intervals with a single signalingevent; and a transmitter coupled to the radio network layer component,wherein the transmitter is configured to transmit information indicativeof the allocated resources to the user equipment.

In another exemplary aspect of the invention, a system includes a userequipment and a base station. The base station is configured to:allocate resources to the user equipment for a plurality of timeintervals with a single signaling event at a wireless network radionetwork layer; and inform the user equipment of the allocated resources.

In a further exemplary aspect of the invention, a circuit includes amanager function configured to allocate resources to a user equipmentfor a plurality of time intervals with a single signaling event at awireless network radio network layer.

In another exemplary aspect of the invention, a wireless networkcomponent includes: a radio network layer comprising means forallocating persistent resources to a user equipment for a data flow; anda communication means between the radio network layer and a physicallayer for informing the physical layer of the allocated persistentresources.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing and other aspects of embodiments of this invention aremade more evident in the following Detailed Description, when read inconjunction with the attached Drawing Figures, wherein:

FIG. 1 shows a simplified block diagram of various electronic devicesthat are suitable for use in practicing the exemplary embodiments ofthis invention;

FIG. 2 shows, in accordance with the exemplary embodiments of thisinvention, an example of periodic allocation of transmission resourcesto one user from persistent resource allocation function that isresident in a Node B Radio Network Layer;

FIG. 3 shows, in accordance with the exemplary embodiments of thisinvention, an example of a hybrid approach where both persistentallocations and one-time (temporary) allocations are applied;

FIG. 4 is a block diagram of a Node B protocol stack that illustratesthe Radio Network Layer that controls making persistent resourceallocations to UEs; and

FIG. 5 depicts a flowchart illustrating one non-limiting example of amethod for practicing the exemplary embodiments of this invention.

DETAILED DESCRIPTION

In an aspect thereof, the exemplary embodiments of this invention reducethe signaling overhead by pre-allocating a pattern of transmissionresources to a particular UE. This procedure may be referred to, in anon-limiting sense, as a persistent allocation or as a semi-staticallocation, and implies an allocation of resources for more than onetransmission interval (e.g., more than one sub-frame). The exemplaryembodiments of this invention pertain to both the physical layer aspectsand to Layer-3 signaling mechanisms to support persistent allocation.The use of the exemplary embodiments of this invention is applicable forboth the uplink (UE to wireless network) and downlink (wireless networkto UE).

The use of the exemplary embodiments of this invention is particularlywell-suited to, and provides enhanced operation for, UTRAN LTE. TheUTRAN LTE relies on OFDMA in the DL and single carrier FDMA in the UL,where a default conventional assumption for both the DL and the UL isthe use of fast scheduling/user multiplexing every 1.0 msec TTI (i.e.,one time allocations). However, it should be appreciated that at leastcertain aspects of this invention have wider applicability, and may beemployed in other types of networks and systems.

Reference is made first to FIG. 1 for illustrating a simplified blockdiagram of various electronic devices that are suitable for use inpracticing the exemplary embodiments of this invention. In FIG. 1 awireless network 1 is adapted for communication with a UE 10 via a NodeB (base station) 12. The network 1 may include at least one networkcontrol function (NCF) 14. The UE 10 includes a data processor (DP) 10A,a memory (MEM) 10B that stores a program (PROG) 10C, and a suitableradio frequency (RF) transceiver 10D for bidirectional wirelesscommunications with the Node B 12, which also includes a DP 12A, a MEM12B that stores a PROG 12C, and a suitable RF transceiver 12D. The NodeB 12 is coupled via a data path 13 to the NCF 14 that also includes a DP14A and a MEM 14B storing an associated PROG 14C. At least one of thePROGs 10C, 12C and 14C is assumed to include program instructions that,when executed by the associated DP, enable the electronic device tooperate in accordance with the exemplary embodiments of this invention,as will be discussed below in greater detail.

The UE 10 is assumed to include and implement a protocol stack 10Econtaining at least layers L1 (PHY), L2 (RLL) and L3 (RNL), andtypically higher layers as well (e.g., an IP layer). As is shown moreparticularly in FIG. 4, the Node B 12 is assumed to include andimplement a protocol stack 12E also containing at least layers L1 (PHY),L2 (RLL) and L3 (RNL), and typically also the higher layers as well(e.g., an IP layer). The L2 (MAC layer) of the Node B 12 includes thefunctionality of a PDCP 32B, and the L3 (RNL) includes the functionalityof a RRC 34A, as discussed in further detail below.

In general, the various embodiments of the UE 10 can include, but arenot limited to, cellular phones, personal digital assistants (PDAs)having wireless communication capabilities, portable computers havingwireless communication capabilities, image capture devices such asdigital cameras having wireless communication capabilities, gamingdevices having wireless communication capabilities, music storage andplayback appliances having wireless communication capabilities, Internetappliances permitting wireless Internet access and browsing, as well asportable units or terminals that incorporate combinations of suchfunctions.

The embodiments of this invention may be implemented by computersoftware executable by the DP 10A of the UE 10 and the DP 12A of theNode B, or by hardware, or by a combination of software and hardware.

The MEMs 10B, 12B and 14B may be of any type suitable to the localtechnical environment and may be implemented using any suitable datastorage technology, such as semiconductor-based memory devices, magneticmemory devices and systems, optical memory devices and systems, fixedmemory and removable memory. The DPs 10A, 12A and 14A may be of any typesuitable to the local technical environment, and may include one or moreof general purpose computers, special purpose computers,microprocessors, digital signal processors (DSPs) and processors basedon a multi-core processor architecture, as non-limiting examples.

In accordance with the exemplary embodiments of this invention, anetwork element, such as the Node B 12, pre-allocates transmissionresources to at least one UE 10, and thus avoids sending a Layer-1allocation table for every allocation per sub-frame. FIG. 2 shows anon-limiting example where transmission resources are periodicallyallocated to a UE 10 in the frequency-time domain. This example assumeslocalized transmission in the frequency domain in the allocatedsub-frames, but it should be realized that the process can begeneralized to cover cases with distributed transmission in thefrequency domain per sub-frame. The example in FIG. 2 illustrates a casewhere only persistent allocation is used for the UE 10. However, asillustrated in FIG. 3, a hybrid approach can also be adapted where bothpersistent allocation and one-time allocation is used. This permitstemporarily increasing the capacity allocation to a UE 10 if the grantedpersistent allocation is found to be insufficient for some relativelyshort (temporary) period of time.

Note that in the example of FIG. 2, the UE 10 is assigned the same bandof frequencies in each consecutive sub-frame, whereas in the example ofFIG. 3, the UE 10 is assigned different frequency bands per sub-frame.

Note should also be made of the fact that the exemplary persistentallocation schemes shown in FIGS. 2 and 3 are both applicable for the ULand/or the DL.

The use of persistent allocations in accordance with the exemplaryembodiments of this invention is particularly well suited for, but notrestricted to, those services that require constant or approximatelyconstant bit rates, such as VoIP and streaming, as two non-limitingexamples, where it is known in advance how many transmission resourcesare needed by the UE 10.

The use of the persistent allocation in accordance with the exemplaryembodiments of this invention provides a signaling scheme compatiblewith UTRAN LTE. Referring to FIG. 4, there is shown a block diagram ofthe Node B 12 protocol stack 12E. Layer 1 (L1) is the physical (PHY)layer 30, Layer 2 (L2) is the MAC layer 32 and Layer 3 (L3) is the RadioNetwork Layer (RNL) 34. Above Layer 3 are typically other layers, agentsand entities, such as an IP layer 36, a QoS agent 38 and a Securityagent 40, that are not particularly germane to an understanding of thisinvention. Various SAPs are shown in FIG. 4 for convenience, as are thevarious control (C) paths (CPDCP, CMAC, CPHY) between the L3 RRC and theunderlying L2 and L1 entities. The PHY layer 30 includes a PHYcontroller/manager function 30A, the Radio Link Layer 32 includes a MACcontroller/manager function 32A and a PDCP controller/manager function32B, and the Radio Network Layer 34 is assumed to include a RRCcontroller/manager function 34A.

In accordance with the exemplary embodiments of this invention, the RRCentity 34A at L3 includes a persistent allocation manager function thatcontrols the persistent allocation of resources to UEs 10. When a newdata flow is set up, the RRC entity 34A decides whether persistentallocation should be used. If persistent allocation is used, then theBTS, which forms a part of the Node B 12, informs the UE 10 of theallocated resources via RRC signaling, as well as the PHY 30A (L1) viaCPHY control messages. This implies that the use of the separate L1signaling to the UE 10 (via an allocation table) for each allocation isavoided, which can provide a significant advantage due to the reductionin signaling overhead.

Since RRC (L3) signaling is utilized to inform the UE 10, the signalingmessage is received at the UE 10 at L3. Information in the receivedsignaling message is subsequently passed on to the UE PHY.

As non-limiting examples, the RRC signaling message and/or the CPHYcontrol message may comprise: a frequency resource(s) ID, a repetitionfactor (e.g., once every X TTIs), SFN mod X (e.g., to “synchronize” theallocation at the Node B 12 and the UE 10), and a hopping sequence(e.g., if the allocated frequency resources periodically change toprovide frequency diversity). In other embodiments, the RRC signalingmessage and/or the CPHY control message may comprise a parameterindicating the “duration” of the allocation. In further embodiments,such a duration parameter may not be necessary because the Node B sendsa specific message to release previously assigned persistentallocations.

The determination by the persistent allocation manager function whetheror not a persistent allocation is used may be based on, as non-limitingexamples, one or more of: the type of data flow being set up (e.g.,VoIP, streaming), any specific QoS requirements of the UE 10 setting upthe data flow, a total number of active UEs in a cell, the types of dataflows (and resource allocations) currently in use by other UEs, and thecurrent load in the network, in particular the DL load caused by L1control signaling (e.g., allocation table). The use of the persistentallocation in accordance with the exemplary embodiments of thisinvention may be particularly advantageous during high load conditions.

To even further enhance the use and flexibility of this approach, theNode-B MAC layer packet scheduler (part of MAC entity 32A) may beenabled to propose new persistent allocations for UEs 10 and/ormodifications of existing persistent allocations to higher or lower datarates. This is desirable since throughput monitoring and bufferinformation is available at the MAC layer 32. However, the persistentallocation manager function that is resident in the Radio Network Layer34 makes the final determination as to whether to comply with thesuggestions received from the L2 MAC entity 32A packet scheduler.

It should also be noted that the persistent allocation manager in L3 mayalso receive inputs from other layers, such as L1 (PHY), that affect thepersistent resource allocation (e.g., channel quality indications). Ingeneral, it may be preferred to make the interface between thepersistent allocation manager functionality and the PHY as generic aspossible, such that the persistent allocation manager function may makeuse of both cell-based and link-based measurements provided by PHY.Other examples of information that may be provided by PHY to thepersistent allocation manager function include, but need not be limitedto, one or both of the load per resource pool (frequency and/or time)and an optimal MCS (Modulation and Coding Scheme) to be persistentlyassigned to a certain UE 10.

Note that this additional embodiment is optional, and is not required toimplement the persistent allocation techniques in accordance with theexemplary embodiments of this invention.

FIG. 5 depicts a flowchart illustrating one non-limiting example of amethod for practicing the exemplary embodiments of this invention. Themethod includes: allocating resources to a user equipment for a dataflow over a plurality of time intervals with a single signaling event ata wireless network radio network layer (501); and informing the userequipment of the allocated resources (502).

In other embodiments, the method further comprises: informing a physicallayer control/manager function of the allocated resources. In furtherembodiments, informing the physical layer control/manager function ofthe allocated resources comprises using at least one CPHY controlmessage. In other embodiments, wherein allocating is performed inresponse to a new data flow being set up. In further embodiments,informing the user equipment of the allocated resources comprises usingradio resource control signaling. In other embodiments, allocatingcomprises considering only information available in the radio networklayer.

In further embodiments, allocating comprises considering, at least inpart, information obtained from at least one layer other than the radionetwork layer. In other embodiments, the information comprises at leastone of: a cell-based measurement, a link-based measurement, a channelquality indication, a load per frequency resource pool, a load per timeresource pool, and a modulation and coding scheme. In furtherembodiments, the information is obtained from a component of a physicallayer. In other embodiments, the information is obtained from acomponent of a medium access control layer.

In other embodiments, the method further comprises: allocating at leastone resource to accommodate fluctuations in radio resource requirementsof the user equipment. In further embodiments, allocating is performedin response to a Node B medium access control layer packet schedulerproposing one of a new allocation or a modification of an existingallocation. In other embodiments, the method further comprises:determining whether a persistent allocation should be used or modifiedfor a respective data flow, wherein allocating comprises in response todetermining that a persistent allocation should be used or modified fora respective data flow, allocating the persistent allocation for therespective data flow. In further embodiments, determining whetherpersistent allocation should be used or modified for the respective dataflow comprises considering at least one of: a type of the respectivedata flow, QoS requirements of a respective user equipment associatedwith the respective data flow, a total number of active user equipmentsin a cell, types of data flows currently in use by other userequipments, resource allocations of the other user equipments, andcurrent load in an associated network. In other embodiments, theplurality of time intervals comprises a plurality of sub-frames.

Based on the foregoing it should be apparent that the exemplaryembodiments of this invention provide a method, apparatus and computerprogram product(s) to provide a persistent allocation manager functionin a Radio Network Layer of a wireless network component for selectivelyallocating resources to UEs for a plurality of sub-frame intervals witha single signaling event so as to reduce an amount of signaling to theUEs. The persistent allocation may be made in accordance only withinformation available in the Radio Network Layer, or in accordance withinformation obtained from another layer or layers, such as the RadioLink Layer. The persistent resource allocation may be made inconjunction with a temporary resource allocation to accommodatefluctuations in radio resource requirements by a particular UE.

As noted above, while the exemplary embodiments have been describedabove in the context of the UTRAN-LTE system, it should be appreciatedthat the exemplary embodiments of this invention are not limited for usewith only this one particular type of wireless communication system, andthat they may be used to advantage in other wireless communicationsystems.

In general, the various embodiments may be implemented in hardware orspecial purpose circuits, software, logic or any combination thereof.For example, some aspects may be implemented in hardware, while otheraspects may be implemented in firmware or software which may be executedby a controller, microprocessor or other computing device, although theinvention is not limited thereto. While various aspects of the inventionmay be illustrated and described as block diagrams, flow charts, orusing some other pictorial representation, it is well understood thatthese blocks, apparatus, systems, techniques or methods described hereinmay be implemented in, as non-limiting examples, hardware, software,firmware, special purpose circuits or logic, general purpose hardware orcontroller or other computing devices, or some combination thereof.

Embodiments of the inventions may be practiced in various componentssuch as integrated circuit modules. The design of integrated circuits isby and large a highly automated process. Complex and powerful softwaretools are available for converting a logic level design into asemiconductor circuit design ready to be etched and formed on asemiconductor substrate.

Programs, such as those provided by Synopsys, Inc. of Mountain View,Calif. and Cadence Design, of San Jose, Calif. automatically routeconductors and locate components on a semiconductor chip using wellestablished rules of design as well as libraries of pre-stored designmodules. Once the design for a semiconductor circuit has been completed,the resultant design, in a standardized electronic format (e.g., Opus,GDSII, or the like) may be transmitted to a semiconductor fabricationfacility or “fab” for fabrication.

Various modifications and adaptations may become apparent to thoseskilled in the relevant arts in view of the foregoing description, whenread in conjunction with the accompanying drawings. However, any and allmodifications of the teachings of this invention will still fall withinthe scope of the non-limiting embodiments of this invention.

Furthermore, some of the features of the various non-limitingembodiments of this invention may be used to advantage without thecorresponding use of other features. As such, the foregoing descriptionshould be considered as merely illustrative of the principles, teachingsand exemplary embodiments of this invention, and not in limitationthereof.

1. A method comprising: allocating resources to a user equipment for adata flow over a plurality of time intervals with a single signalingevent at a wireless network radio network layer; and informing the userequipment of the allocated resources.
 2. The method of claim 1, furthercomprising: informing a physical layer control/manager function of theallocated resources.
 3. The method of claim 2, wherein informing thephysical layer control/manager function of the allocated resourcescomprises using at least one CPHY control message.
 4. The method ofclaim 1, wherein allocating is performed in response to a new data flowbeing set up.
 5. The method of claim 1, wherein informing the userequipment of the allocated resources comprises using radio resourcecontrol signaling.
 6. The method of claim 1, wherein allocatingcomprises considering only information available in the radio networklayer.
 7. The method of claim 1, wherein allocating comprisesconsidering, at least in part, information obtained from at least onelayer other than the radio network layer.
 8. The method of claim 7,wherein the information comprises at least one of: a cell-basedmeasurement, a link-based measurement, a channel quality indication, aload per frequency resource pool, a load per time resource pool, and amodulation and coding scheme.
 9. The method of claim 7, wherein theinformation is obtained from a component of a physical layer.
 10. Themethod of claim 7, wherein the information is obtained from a componentof a medium access control layer.
 11. The method of claim 1, furthercomprising: allocating at least one resource to accommodate fluctuationsin radio resource requirements of the user equipment.
 12. The method ofclaim 1, wherein allocating is performed in response to a Node B mediumaccess control layer packet scheduler proposing one of a new allocationor a modification of an existing allocation.
 13. The method of claim 1,further comprising: determining whether a persistent allocation shouldbe used or modified for a respective data flow, wherein allocatingcomprises in response to determining that a persistent allocation shouldbe used or modified for a respective data flow, allocating thepersistent allocation for the respective data flow.
 14. The method ofclaim 13, wherein determining whether persistent allocation should beused or modified for the respective data flow comprises considering atleast one of: a type of the respective data flow, QoS requirements of arespective user equipment associated with the respective data flow, atotal number of active user equipments in a cell, types of data flowscurrently in use by other user equipments, resource allocations of theother user equipments, and current load in an associated network. 15.The method of claim 1, wherein the plurality of time intervals comprisesa plurality of sub-frames.
 16. A computer program product comprisingprogram instructions embodied on a tangible computer-readable medium,execution of the program instructions resulting in operationscomprising: allocating resources to a user equipment for a data flowover a plurality of time intervals with a single signaling event at awireless network radio network layer; and informing the user equipmentof the allocated resources.
 17. The computer program product of claim16, wherein execution of the program instructions results in operationsfurther comprising: informing a physical layer control/manager functionof the allocated resources.
 18. The computer program product of claim16, wherein allocating is performed in response to a new data flow beingset up.
 19. The computer program product of claim 16, wherein informingthe user equipment of the allocated resources comprises using radioresource control signaling.
 20. The computer program product of claim16, wherein allocating comprises considering, at least in part,information obtained from at least one layer other than the radionetwork layer.
 21. The computer program product of claim 20, wherein theinformation comprises at least one of: a cell-based measurement, alink-based measurement, a channel quality indication, a load perfrequency resource pool, a load per time resource pool, and a modulationand coding scheme.
 22. The computer program product of claim 20, whereinthe information is obtained from a component of a physical layer. 23.The computer program product of claim 16, wherein allocating isperformed in response to a Node B medium access control layer packetscheduler proposing a new allocation or a modification of an existingallocation.
 24. The computer program product of claim 16, whereinexecution of the program instructions results in operations furthercomprising: determining whether a persistent allocation should be usedor modified for a respective data flow, wherein allocating comprises inresponse to determining that a persistent allocation should be used ormodified for a respective data flow, allocating the persistentallocation for the respective data flow, wherein determining whetherpersistent allocation should be used or modified for the respective dataflow comprises considering at least one of: a type of the respectivedata flow, QoS requirements of a respective user equipment associatedwith the respective data flow, a total number of active user equipmentsin a cell, types of data flows currently in use by other userequipments, resource allocations of the other user equipments, andcurrent load in an associated network.
 25. A device comprising: a radionetwork layer component configured to allocate resources to a userequipment for a plurality of time intervals with a single signalingevent; and a transmitter coupled to the radio network layer component,wherein the transmitter is configured to transmit information indicativeof the allocated resources to the user equipment.
 26. The device ofclaim 25, wherein the radio network layer component is furtherconfigured to inform a physical layer control/manager function of theallocated resources.
 27. The device of claim 25, wherein informing theuser equipment of the allocated resources comprises using radio resourcecontrol signaling.
 28. A system comprising: a user equipment; and a basestation configured to: allocate resources to the user equipment for aplurality of time intervals with a single signaling event at a wirelessnetwork radio network layer; and inform the user equipment of theallocated resources.
 29. The system of claim 28, wherein the basestation is further configured to inform a physical layer control/managerfunction of the allocated resources.
 30. The system of claim 28, whereininforming the user equipment of the allocated resources comprises usingradio resource control signaling.
 31. A circuit comprising: a managerfunction configured to allocate resources to a user equipment for aplurality of time intervals with a single signaling event at a wirelessnetwork radio network layer.
 32. The circuit of claim 31, wherein themanager function is further configured to: inform the user equipment ofthe allocated resources.
 33. The circuit of claim 32, wherein themanager function is further configured to: inform a physical layercontrol/manager function of the allocated resources.
 34. The circuit ofclaim 32, wherein informing the user equipment of the allocatedresources comprises using radio resource control signaling.
 35. Awireless network component comprising: a radio network layer comprisingmeans for allocating persistent resources to a user equipment for a dataflow; and a communication means between the radio network layer and aphysical layer for informing the physical layer of the allocatedpersistent resources.
 36. The wireless network component of claim 35,wherein allocating comprises considering, at least in part, informationobtained from the physical layer.
 37. The wireless network component ofclaim 35, wherein allocating comprises considering, at least in part,information obtained from a medium access control layer.